Control mechanism for aeroplane superchargers



sm E6, 29124.

R. G. STANDERWHCK CONTROL MBCHANISM FOR ABROPLAWB SUPBRCHARGBRS mies Apru a, 1922 nd/d 62 dnae/wc/f,

BEGINLD G. STANDEBWIGK, 0F LYNN,

turenA STATES.-

Ila'rlsrrr omer..

nnss'acnusnr'rs, Assrononp'ro'onmat Etnea-arc country, A conromrmn or new Yonx.

CUNTML lMliiCHAN'I-SM F03 .AEBOPLANE SUPERJGHABGEBS.

Application ledpril 8, 1922. Serial No. 550,982.

To all whom it may concern;

Be it known that` I, REGINALD G. vSTAN- nnRWIcK, a citizen of the' United States, residing at Lynn, in the kcountyof Essex, State of Massachusetts, have 'invented certain new and useful Improvementsin Control Mechanism 4for `Aero lane Superchargers, of which the following is a speciburetors of the 'engine. In connection with the use of superchargers it is advisable that the .regulation of the supercharger. be under the control of the aviator tio a certain .25 degree.- It is desirable, however, that the arrangement be such that at lower altitudes the aviator cannot supercharge above a predetermined high lpressure,"a thing likely to cause preignition, while at hi her altitudes,

it is desirable that the'superc arger be not overloaded in its efforts to maintain 'the desired su ercharger pressure. For example,

a su rc arger designed to provide air at sea evel pressure at an -altitude of 20,000

'feet might be overloaded and damagedy if it be attempted to make it provide air 'at sea level pressure at an altitude of 30,000 feet.

On the other hand, at an altitude of 10,000

feet thesupercharger-would be capable of 40 compressing air to a pressurehi'gher than it would be advisable to use in the engine.

More particularly, the object of my in,

vention is' to lprovide an improved regulating or contro ing mechanism which, while leaving the control of the supercharging primarily in the hands of the aviator, will prevent automatically either over supercharging or overloading of the' supercharger.

ln the drawing, Fig. 1 is a diagrammatic plan view of an aeroplane engine equip ed with a supercharger having a c ontroLmec auism embodying my invention, and Fig. 2

. l invention relates to super-- is a sectional view of certain parts together with a diagrammatic view of the electrical clrcuits. In the present. instance I have shown my invention carried out in connection with 4a supercharger of the type comprising. a centrifugal compressor driven by a turbine which in turn is operated by exhaust ses from the aeroplane engine, the lilo'w o exhaust gases 'to the turbine being regulated -by valve means controlling the flow of exhaust gases to atmosphere, this being a known arrangement. It will be understood, however, that the invention ma be carried out in connection with any desired type of supercharger drive. .A

Referring to th drawing,5 indicates cylinders of an aeroplane internal combustion engine, 6 indicates intake pipes, and 7 indi- 'cates exhaust pipes, there being arr-intake pipe and an exhaust pipe for each cylinder.

The intake pipes 6 are connected tocarburetors indicated diagrammatically at 8. Air is supplied to carburetors 8 from a man-. ifold 9 connected by -pipes 10 to the discharge side of the supercharger 11. TheV supercharger is shown diagrammatically only but it will be understood that it may comprise a suitable centrifugal'compressor which takes air from the atmosphere,'compresses it, and. delivers it to the pipes 10, the

air inpassing through the Y ipes 10 being.

cooled prior to', delivery to 't e carburetors. The compressor may be 4driven by a turbine wheel actuated by exhaust Agases 'from the engine cylinders and t this end exhaust pipes 7 are connected to a manifold 12'which at one end is open tothe atmosphere and at the other end connects lwith a casing 13 having a suitable nozzle box in which are nozzles for .directin the exhaust gases to the turbine wheel. e specific structure of the turbine. and compressor forms no part of the present invention and they are accordin l indicated diagrammatically onl The g y 'fold 12 to iiow of exhaust gases from man1 the turbine nozzles is regulated by valve 14. at the open end of thelexhaust manifold 12. When valve 14 is closed all the exh'aust gases will be delivered to the turbine while f when the valve 14 is vopen the exhaust gasesf105 will discharge directly to atmosplhereand only a small amount will be supp ed'to the by a link 18 to the core 19 of a solenoid,` the winding of which is indicated at 20.

Core 19 slides in a sleeve 21 withV which it makes a close fit, andthe in ner open end of the sleeve is coveredby a head 22 in {Lhch is a vent 23, the area of which -can re suitab y fastened to the shell S25 of the solenoid. Formed integral with arms 15.

and 17 is a third arm 26 provided with a pin' 268L at its end which rides in a slot 26" formed in a link 26. Link 26 is pivotall 'connected at one end to one arm of a bel crank lever 26", theother arm of which is connected to, a rod '26 which terminates at a point within, the reach of the aviator and which is used by him for manually opening the valve 14. Bell crank lever 26l is pivoted at ,its elbow on a fixed, post 26. In the present instance I have shown onl one half of the aeroplane engine It wil be understood that in the particular instance there will be a second `row of cylinders connected to the carburetors by pipes 27 and discharging to an exhaust manifold, tle duplicate of that shown at 12, and arranged particular in exactl Ythe same way, except that its outer en instead of being provided with a blast -gate or valve such as 14, is closed. In other words, the particular engine illustrated is of a twelve-cylinder V-type arrangement such as is in common use in aeroplanes.

The portion of the engine shown is suiii-A cient to illustrate my mvention since the type of engine does not enter into it.

Referring now particularly to Fig. 2, I provide in connection with the manifold 9 a casing 28 which communicates thro, h an vopening 29 with manifold 9. In tie .present instance the casing is shown as being bolted directly to a wall of manifold- 9. n casing 28- is arranged a diaphragm 30 providing a sealed chamber 31. Carried by diaphragm 30 is a contact 32 adapted to engage a contact 33 carried by, but insulated from, casing. 28. Contact 32 asses through a suitable fixed guide 34 and as on its end an adjustable collar 35 between whichand 'guide 34 is arranged.- a coiled spring 36, Iwhich acts in a direction tendingt'o move contact 32 into engagement'with contact 33. By -adjusting the tension of spring 36 the pressure at which diaphragm 30,w1]1 move can be varied.

Sealed chamber 31 may or may. not con-I the diaphragm lated by a screw 24. Head 22 ismospsi tain a certain amount of air, depending on the operating condition desired. If the chamber contains a certain amount of air, will be responsive to both the temperature and the pressure of the air delivered by the slpercharger. Iii it is desired to have the laphragm respond to ressure only the chamber 31 will be exusted of air. AIn'any event the ,arrangement is'such that the air pressure in' chamber 31, if any, plus the force ofspring `36 is such thatl diaphragm 30fwillbe'moved tc separate contacts 32 and when the pressure on it reaches the` desired maximum supercharger pressure, for example, sea level atmospheric pressure. f Y

Connected -tc manifold 9 is a second caslng 37 which is open at 38 to atmosphere. i ing 37 comprises a cover plate 39 wh1ch 1s fixed over anopening in a wall. of manifold 9, and carried by plate 39 are two spaced concentric diaplhragms 40 and 41. At one end these diap and at the other end they are fixed to a head 42. The air is exhausted from 'the annular space l '.43 formed between dia.- phragms 40 and41, and' in such space 1s Casragms are fixed to plate 39 Y an annular wall 44 which forms a' stop to l hold the dia hragms from collapsing beyond predeterx'nlined` amount. Annularwall 44 may be fixed to head 42. AIn wa 44 are one or more openings 45 in order that the preure in chamber 43 will be uniform. The interior of diaphragm 40 commumcates through an opening 46 in plate39 with manifold 9 so thatthe interior of diaphragm40 and the rtion of head 42 directly over it-are subjected on'theini'nner surfaces to the super- .charger pressure. The outer surface -of head 42 is subjected over its entire. area to altitude atmospheric pressure. Fixed v on plate 39 is a post 47 which carnes at its upper end a contact 48 insulated from the post as indicated at 49, and carried by head 42 and suitably insulated therefrom 1s a second contact 50 adapted to engage contact 4 8.

The area of head 42 subjected to altitude atmospheric pressure bears vsuch relation to the area subjected to supercharger pressure that as long as the' ratio between` such ressures does notexceed a predetervalue, contacts 48 and 50 remain 1n late 39 but `s not fixed to loal gement. When the ratio exceeds this en va ue,however, diaphragms 40 and 41 will `be expanded and will move contact 50 from At 51 is a en gement with contact 48.

sulta le source of electrical energy, such as a storage battery. The terminals of solenoid 20 are indicated at 52 and 53 and they are connected inI a circuit comprising wire 54,

battery 51, Wire 55, contact 50, contact 48,

lwire 56', contact 33, contact 32, wire 57,

switch 58 and wire 59 to terminal 53.

p When the foregoing circuit is closed, the solenoid will hold blast gate or valve 14 closed while when the circuit is opened spring 14 will move valve 14 toward open position. The closin and openin movements of valve 14 are ampened byt e'dash-y pot ei'ect produced'by core 19 moving in sleeve 21, screw 24being adjustable to make the areak of vent 23V such that the desired dampening of the movements is obtained.

The operation is as follows: The electric circuit through contacts 32, 33 and 48, 50 being closed, solenoid acts to pull valve .14 closed against the action of spring 14,

the solenoid being suiliciently strong to overcome the action of the spring. However, valve 14 can be opened manually by hand control rod 26 against the action of vthe solenoid.v Assuming valve 14` is closed all the exhaust gases from the en ine wil be directed to the turbine whee of the supercharger whereby it will. be operated to supply supercharged air to the engine. As soon, however, as the supercharger pressure exceeds the desired maximum value, dia.

'phragm 30 will be moved to bring contact 32 from engagement with contact 33 thus breaking the circuit through solenoid 20 whereupon spring 14 will. move vali-re 14 toward open position, the movement being dampened by the dashpot eii'ect of core..19l

in sleeve21.' Opening of valve 14.will permit exhaust gases to escape directly to atmosphere which will effect a slowing down of the speed of the supercharger anda decrease in `the supercharger pressure. soon as` the supercharger pressure )comes again to avalue below, the maximum, con-k tact 32l-will move again into engagement.

pressure with contact ,63 closing' the' circuit 'through solenoid 20 which willlmove valvev 14 toward closed position, such movement being damp-v cned by the dashpot eiect already referred to. Thus the supercharger-pressure will bev a ain increased. It will thus be seen thatv diaphragm forms a deviceresponsive tov the supercharger pressure which acts automatically to maintain the supercharger pressure at a desired maximum value.

In case the ratio between the supercharger and the -altitude. atmosp eric pres-` sure exceeds the desired predetermined value, a thing which may occur at high' altitudes, the supercharger pressure acting on the innersrface of head 42 within diaphragm 40 will expand diaphragme 40 and 41l thus lifting contact 50 from engagement with contact 48 which will open'the circuit. of solenoidl 20` and. permit .spring 14 to pull valve 14 towar open position'thus effecting a decrease in the supercharger pressure. Diaphragms 40, 41 thus form a diierential pressure device which serves to" prevent the ratio between the supercharger air pressure and the altitude atmospheric pressure from exceeding a predetermined value. The supercharger pressure ratio is.

'mediate position to obtain a desired amount of supercharging as lon as it is below the maximum amount for w 'ch diaphragm 30 is set. When this maximum is reached, the controlwill be taken away from the aviator and the pressure automatically prevented vfrom exceeding the desired maximum;

In accordance with the provisions of the patent statutes, I have described the principle of operation ci my, invention, together witlifthe apparatus .which I now' consider to represent the best embodiment thereof,

but I desire to have it understood that theJ apparatus shown is only illustrative and that "the invention' may be carried out by other-means. y

What I claim asnew and desire -to secure.

by Letters Patent of the United States is 1. In combination, an internal combustion engine, a supercharger for supplying compressed air thereto, regulating means for the supercharger, electromagnetic operating means for said regulating means; an

electric vcirc'zuit therefor, vand Ymeans responvsive-to the-supercharger. air lpressure and to the ratiov betwenf-thepsupercharger air pressure a dll the l'altitude,yatmospheric pressure for controlling, saidl electric circuit.- Y ,fl-2.5111 -combinationf-,- 1an, internal combustion engine, a supercharger-for supplying compressedvair' thereto,-"aivalvefor regulat ,ingthesi'iperchargeja solenoid having its core connected to the vaive, and an electric circuit 'for the solenoid, 'which 'is controlled by vther superchargerl pressure and; by the lratio between x the.. supercharger t pressure and the altitude. atmospheric pressure.

3. The combination 'with -an aeroplane having an internal combustion engine,- a.

supercharger supplying air to the, engine, and means for controlling the superchar er, of operating means for said control ing means comprising a solenoid having its core connected to the controlling-means, 'an

velectric circuit for the solenoid, a movable `member responsive to the supercharger air pressure controlling said cii/cuit, and a second movable member responsive to the ratio 1 between the supercharger air pressure and thev altitude air pressure controlling said 'circuitj.V y y r4. In combination, an internal combus-4 tion engine a supercharger for supplying compressed ,a',ir,'thereto, a valve for regulate ing the supercharger, a solenoid having its core connected to 'the va1ve,'a spring connected to thevalve for biasing it toward a. position to decrease the s d of the super- Y charger, an electric circult for the solenoid, and contact means responsive to the supercharger air pressure and to the 'ratiobetween the supercharger air pressure 'andthe 10 l REGINALD G; STANDERWICK.

altitude atmospheric. pressure for control- 

